<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <ul id="rarent">
        <li class="child">one</li>
        <li class="child">two</li>
        <li class="child">three</li>
    </ul>
</body>
</html>
<script type="text/javascript">
//获取父元素
var dom = document.getElementById('rarent')

dom.onckick = function (event){
    var event = event || window.event
    var ct = event.target || event.srcElement;
    if(ct.tagName.toLowerCase() == 'li'){
        //要处理的事件
    }
}

</script>